Delaware Coastal Zone Act: What It Actually Restricts

What CZA actually prohibits

The statute's clear prohibitions, unchanged since 1971 enactment:

• New heavy industry. Construction of new heavy industry of any kind not in operation on June 28, 1971 is prohibited within the defined Coastal Zone. Examples called out in the law and implementing materials: oil refineries, paper mills, incinerators, steel manufacturing plants, liquefied natural gas terminals.
• New offshore bulk product transfer facilities. New offshore gas, liquid, or solid bulk product transfer facilities not in operation on June 28, 1971 are prohibited due to pollution risk.
• Offshore drilling. Offshore drilling for oil and natural gas is prohibited in the coastal zone and other state waters.

These are the core restrictions. Notice what's not on this list.

What CZA does not prohibit — and often surprises developers

CZA does not restrict:

• Hotel, motel, B&B, and vacation rental construction.
• Restaurants, bars, and food service.
• Retail, shopping, and mixed-use commercial.
• Residential (single-family, multi-family, townhome, condo).
• Recreational amenities — pools, mini-golf, boardwalk attractions.
• Adaptive reuse of existing buildings.
• Office, professional services, medical-office-scale commercial.
• Light industrial uses that don't meet the "heavy industry" threshold.

Where CZA matters for non-industrial commercial development is indirect — by preventing heavy industrialization, it preserves the recreation/tourism character of the coast that supports ordinary commercial investment. Developers building a hotel in Rehoboth shouldn't expect CZA to be the controlling regulatory body; it isn't. Zoning, building code, stormwater, wetlands/floodplain, and the Beach Preservation Act (for work on beaches proper) are the controlling frameworks.

The Coastal Zone geography

The statutorily-defined Coastal Zone includes areas along:

• The Delaware River
• Delaware Bay
• Chesapeake & Delaware Canal
• Atlantic Ocean
• The Inland Bays

The Zone can extend up to two miles inland in certain areas depending on precise boundaries set by the Act and subsequent amendments. A project in Lewes, Rehoboth, Dewey Beach, Bethany Beach, or Fenwick Island is geographically within the Coastal Zone — but that alone doesn't trigger CZA review unless the project fits the heavy industry or bulk-transfer categories.

Grandfathered industrial sites

Fourteen specific sites were in operation on June 28, 1971 and are "grandfathered" — allowed to continue their pre-1971 heavy industrial use. Thirteen of the fourteen are in New Castle County (the Delaware River / Delaware Bay industrial corridor). One is elsewhere. These sites are the only locations where heavy industry can exist inside the Coastal Zone.

Sussex County — where the tourism-driven beach towns are — has essentially no grandfathered heavy industrial sites. This is why CZA's industrial restrictions have essentially no impact on Rehoboth / Lewes / Dewey Beach commercial development: there was no heavy industry there to grandfather, and new heavy industry isn't allowed.

The 2017 conversion permit amendments

House Bill 190 of 2017 created a "conversion permit" process allowing the 14 grandfathered sites to convert between heavy industrial uses — effectively allowing a grandfathered site that was (say) a historic refinery to be reused for a different heavy industrial purpose. The rationale was economic development on sites that already carry industrial infrastructure (rail, port, utilities) but whose original use is no longer viable.

Conversion permits:

• Apply only to the 14 grandfathered sites.
• Allow change of heavy-industrial use, not expansion into previously-undeveloped coastal land.
• Require DNREC permitting with specific environmental performance criteria.
• Include public review and comment.
• Don't relax the core CZA prohibition on new heavy industry on non-grandfathered land.

For Sussex commercial development, the 2017 amendments are not operative — the sites are in New Castle County.

What does apply to Sussex coastal commercial construction

A developer building a hotel in Rehoboth or a restaurant in Lewes engages these frameworks (not CZA):

• Local zoning — city zoning (Rehoboth, Lewes, Dewey, etc.) and Sussex County zoning outside city limits.
• Delaware State Building Code as adopted locally.
• Sussex Conservation District stormwater plan review (see our DE Conservation District essay).
• DNREC Wetlands and Subaqueous Lands permits for work affecting tidal wetlands, subaqueous lands, or navigable waters.
• Beach Preservation Act for work on beaches, dunes, or beach-adjacent property (7 Del. C. Ch. 68 — distinct from CZA).
• Floodplain ordinances — local FEMA flood-zone compliance for construction in V, A, and coastal A zones.
• DelDOT for access points on state-maintained roads.
• Public utility coordination for water, sewer, power.

The Beach Preservation Act in particular is often confused with CZA. It's a different statute under a different chapter of Title 7 and regulates different activities (beach/dune protection vs coastal industrial restriction).

When CZA becomes relevant outside heavy industry

There are specific non-industrial scenarios where CZA can come up:

• Large-scale energy infrastructure. Offshore wind substation landing, LNG facilities, major gas pipelines interacting with coastal areas.
• Port-related infrastructure. New bulk transfer at Port of Wilmington or similar coastal port facilities.
• Aggregate industrial projects. Facilities arguably fitting "heavy industry" definition even if marketed differently.
• Expansion of grandfathered nonconforming uses. Requires DNREC permit; applicable to the 14 grandfathered sites only.

For the common Sussex developer/contractor, these are not the usual project types. For developers and engineers working on major coastal-adjacent industrial or infrastructure projects, CZA analysis is part of schematic design.

Administration

DNREC administers CZA through its Coastal Programs division. Permitting and enforcement sit within DNREC; advisory input from the Coastal Zone Industrial Control Board is part of certain processes.

Primary sources:

• dnrec.delaware.gov/coastal-programs/coastal-zone-act-program/ — program page.
• dnrec.delaware.gov/coastal-programs/coastal-zone-act/history-of-the-coastal-zone-act/ — historical context.
• delcode.delaware.gov/title7/c070/ — statute text.

Common misconceptions

• "We're building in the Coastal Zone so we need CZA approval." Not unless it's heavy industry or bulk transfer.
• "CZA replaces zoning near the coast." No; local zoning remains fully in effect.
• "CZA is why Rehoboth restricts development." No; local zoning and the Beach Preservation Act are the controlling frameworks there.
• "Conversion permits let anyone build heavy industry." No; only the 14 grandfathered sites can use conversion permits, and only to swap one heavy industrial use for another.
• "CZA is the wetlands law." No; DNREC's Wetlands Program under 7 Del. C. Ch. 66 is a separate framework. Tidal wetlands work requires its own permit regardless of CZA.

What to do with this

If you're developing non-industrial commercial in Sussex coastal towns: understand CZA doesn't apply to your typical project. Focus on local zoning, state building code, Sussex Conservation District stormwater, DNREC wetlands/subaqueous permits if applicable, and Beach Preservation Act for beach-adjacent work.

If you're working on a coastal industrial project: CZA is likely the core regulatory question, and the 14-site grandfathered list is the starting point for what's possible. Engage DNREC Coastal Programs early.

If you're a contractor/designer needing to rule out CZA applicability: DNREC can provide a written scope determination for borderline projects. Don't speculate; get the determination.

For cross-state coastal/environmental comparison, see Mid-Atlantic Stormwater Compared and our Delaware Stormwater Navigator.

About The Hive

The Hive builds tools and publishes essays for working construction and MEP professionals in the Delaware Valley and Mid-Atlantic. Primary-source-grounded, practitioner-voiced, free to use.